New Super Mario Bros. 2 continues the style of gameplay from New Super Mario Bros., featuring side-scrolling platform action as Mario or Luigi attempt to rescue Princess Peach from Bowser and his Koopalings. Along with returning power-ups from the first game, such as the Mini Mushroom and Mega Mushroom, the game also sees the return of the Super Leaf from Super Mario Bros. 3, allowing the player to tail whip enemies or fly up into the air. Similar to Super Mario 3D Land, an Invincibility Leaf will appear if the player dies at least five times during a stage, granting raccoon abilities and invincibility until the end of the stage. The main game has both single player and multiplayer options: two players, each with his or her own Nintendo 3DS and copy of the game, play together simultaneously as Mario and Luigi. Like the previous games, players can collect Star Coins hidden throughout each level, which can be spent to unlock new areas on the overworld map.

The game has a strong emphasis on collecting gold coins, with various new items dedicated to producing large amounts of coins. These include Gold Flowers that turn blocks into coins, rings that temporarily turn enemies gold and a block mask that produces coins as Mario runs. The game keeps track of all coins collected by the player and displays the total on both the title screen and on the overworld map. If the player has SpotPass enabled in the game, this total can be uploaded to Nintendo Network and the player will be updated with the grand total of all coins collected by all players worldwide.

In addition to the main game, New Super Mario Bros. 2 features a Coin Rush mode, unlocked after the player completes the first world. In Coin Rush, the player plays through three randomly chosen levels collecting as many coins as possible. However, the player is given only one life and each level gives a time limit of 50 or 100 seconds. The 1-up Mushrooms are replaced by Gold Mushrooms in this mode. If mid-way flags are passed or timers are collected, the time limit will be extended. If the player completes the run, the accumulated total of coins collected can be saved as the player's high score, which can be transmitted to and challenged by other players via StreetPass. Additional course packs can be purchased as downloadable content. [Source: wiki]